In hard rock mining application, it is common to use, for example, rock shearers for winning hard rock materials in a longwall, or to use, for instance, rock headers for generating a roadway in an underground mine. Both the rock shearer and the rock header may comprise at least one rotatable drum, which may be equipped with at least one cutting head being rotatable. The cutting head may be configured to support a plurality of cutting bits which are in turn configured to engage the hard rock for winning hard rock materials. The rotatable drum may be adjustable in height relative to a machine frame by a swivel arm.
The rotatable cutting head may include a cone-like shaped body having cutting bit carriers integrally formed with the body. Thus, known cutting heads may be manufactured as an integral unit, wherein worn cutting bits may be replaced by newly manufactured cutting bits. The cutting bits are rotatably and removably supported by the cutting bit carriers.
For example, EP 2 208 856 A2 discloses a cutting head having a plurality of cutting bits for wining underground materials.
US 2011/0089747 A1 relates to a cutting bit retention assembly that includes a cutting bit holder, which receives a cutting bit and has shank that extends into a bore in a support. The shank section of the cutting bit holder presents a surface defined by a notch that selectively cooperates with a retention pin.
US 2010/0001574 A1 discloses an apparatus for the milling and/or drilling cutting of materials, in particular for the removal of rock, minerals or coal, with a tool drum which is mounted on a drum carrier rotatably about a drum axis, in which a plurality of tool shafts, which carry cutting tools at their ends projecting from the tool drum, are rotatable drivable mounted, at least two of the tool shafts being drivable by a common gear drive and a common drive element.
An apparatus for the milling cutting of rock, minerals or other materials is known from WO 2012/156841A2. The disclosed apparatus includes two tool drums, which are arranged rotatably mounted side by side in twin arrangement on a drum carrier and which are respectively provided with a plurality of tool carriers which support cutting tools.
U.S. Pat. No. 3,647,265 A discloses a rotary drum-type cutting head for use with mining and tunneling machines. The cutting head includes a cylindrical drum to the periphery of which are secured a number of arcuate segments provided with pick boxes for the reception of picks.
US 2008/0116734 A1 discloses a device for milling rock or other materials. The device comprises a spindle drum which is rotatably mounted on a drum support and in which a plurality of tool spindles are received to be rotatable about spindle axes in a manner off-center of the drum. At least two of the tool spindles can be driven by a common gear drive which comprises output gears.
U.S. Pat. No. 3,326,307 A discloses a rock bit roller cone having a peripheral notch, and an annular band seated fast in said notch having a succession of radially extending cutter teeth about its peripheral surface.
Mechanically locked drill bit components are known from U.S. Pat. No. 5,906,245 A, and a cutter assembly including rotatable cutting element and a drill bit using the same are known from U.S. Pat. No. 7,762,359 B1.
The present disclosure is directed, at least in part, to improving or overcoming one or more aspects of prior systems.